One-winged Angel of Gremory
by Dante Fernandez
Summary: Aiko Nonaka; a girl with a bad attitude and considered to be the pariah of Kuoh. She cares for nothing & no one except for her precious sister; she was content with the life she had till a fateful incident that changed her current life forever. Now a servant of Rias Gremory she now has more reason to fight... to live.
1. Legacy

_Prologue_

 _Many millennia ago, there lived an ancient race who carried the very lifeblood of Gaia herself. The Cetra, a race of beings who were meant to be the guardians of the planet and maintain the balance between the three realms themselves. They were a peaceful race, living sages who had power that one could only imagine. However one day a beast of immense power known only as Jenova came to Gaia from the eternal abyss of space, her only goal was to drain the lifeblood of Gaia and devourer the planet. The Cetra gathered to combat this great threat; many lost their lives to the great beast and the battle lasted for years. Try as they might they stood no chance against her power. With no option left they gathered all their remaining power into separating Jenova into Seven pieces and sealing those pieces into places where neither life nor death could ever hope to reach._

 _Now that the Cetra were practically extinct the forces of heaven and hell fought against each other for the right to claim the Third Kingdom. Yahweh, realizing this took the life-force of Gaia and created the first humans and proclaimed them as rulers of the Third Kingdom. However he did not realize that Jenova's presence had corrupted the planet and thus the humans became corrupted as well._

 _One such human, named Trihexa, had bathed in so much corruption that she was able to hear the voice of Jenova which drove her further to insanity. She proclaimed herself as a daughter of Jenova and seek to free her 'mother' from her prison. Through finding the 'blood' of Jenova inside of the Lifestream she drank it and gained unimaginable dark power that could rival if not surpass the Cetra themselves and was called the Beast. Though she could not find a way to free her 'mother's' body she had found a way to free her soul by allowing her to possess her through the Lifestream._

 _In honour of her 'daughter's' sacrifice she took up her name; Jenova was free once again to reek havoc upon the world and was proclaimed as the Emperor Beast of the Apocalypse. Yahweh seeing this had no choice but to fight the Beast as the Cetra were no more; the battle was even fiercer than the previous one, despite being seemingly matched Yahweh was loosing ground to the more powerful dark deity and he realized that it was impossible to kill her. With no choice he used all his remaining power to rip her soul out and seal it with 1000 forbidden class seals so she could never be free or even influence another victim ever again, no matter how corrupt they are._

 _However the cost was high, Yahweh soon died from exhaustion leaving Heaven leaderless and without their father. He died happily knowing that Trihexa will no longer be able to reclaim her freedom once more; though what he did not realize was that the lifestream was still corrupt with her influence and that he had completely forgotten about the corpse of Trihexa who's flesh and blood will continue to be used to create more like her for centuries to come…_

* * *

A little girl no older than six was waiting next to a closed door with an expressionless face despite the screams of pain coming from within. The little girl had long pink hair with a streak of silver in the middle, her eyes were a dark purple colour with flecks of emerald green in them and were strangely enough slitted like that of a cat's… or a snake.

Her face showed a level of maturity & emotionless that no child should ever have even though her mother was currently in tremendous pain from giving birth.

Eventually the cries of pain had ceased and were replaced by the cries of a newborn.

The door opened revealing a maid who looked quite relieved.

"Come mistress Sephirah, your mother awaits."

The little girl named Sephirah simply followed the maid.

Inside were two more maids who were attending a woman laying down on a bed and holding two small bundles closely to her breasts. The woman, despite her exhaustive state, had such an unearthly beauty that many would think she was actually a goddess of beauty. She had long bright pink hair that reached to her knees, bright violet eyes full of life unlike her daughter's dark purple dead-like eyes, and her body was quite shapely with large sized breasts that women would kill to have.

"Sephy… come here and greet your new sisters."

Sephirah approached and peered curiously at the two bundles.

Two identical twin baby girls with very short pink hair though only one was crying like a normal newborn should while the other was too quiet and if it weren't for the deep breathing she would think that she was dead.

Unconsciously she reached out to her sisters; the cryer stopped crying and remained silent, while the seemingly unhealthy one started whimpering. Eventually when her hand got too close, the sickly one whimpered even louder and tears started forming in her eyes.

The mother flinched, while Sephirah retracted her hand.

"Sephy… please don't…"

It was too late as she quickly turned to leave… Or at least would have if it weren't for something tugging at her hair.

She turned back and was surprised to see her other sister holding her hair.

With a grunt of annoyance she quickly let out some killing intent, causing the maids to gasp in fright and for the sickly sister to whimper & cry some more. Yet the brave sister simply… glared at her(?) and puffed her cheeks in annoyance.

Baffled, she once again got close and tried to pry her little sister's hands of her hair only for her to quickly grab tightly to her finger. Sephirah swore that she was giving her a smug look that said 'you can't get rid of me that easily.'

Her heart was thumping quickly with unknown emotions. She didn't know why but she slowly grabbed her from her mother's arms and into her own.

Slowly the newborn opened her eyes, revealing a bright violet like her mother's, and when she gazed upon her older sister's face… she smiled; her eyes filled with nothing but love & happiness for her sister.

Sephirah looked at her stunned, not knowing what to make of this. This was not the look of fear, horror or disgust that she was so used to seeing from others.

Her heart beated faster and tears started forming in her eyes.

'I don't understand… why…?'

Her thoughts were interrupted as her little sister stopped smiling and frowned. At first Sephirah thought that her little sister came to her senses, however instead she raised her pudgy little arms at her. She was confused on what her little sister was demanding while her little sister puffed her cheeks in annoyance and started to whine.

Finally figuring out what she wanted, she brought her slowly towards her face and when she was close enough her little sister instantly started rubbing her hands right under her eye. Sephirah was confused until she realized what she was doing… she was rubbing her tears away.

At this realization more tears poured out of her eyes.

'Why…? Why don't you fear me? Why don't you hate me? Why… do you love me?'

The little sister tenderly rubbed her face on her older sister's cheek.

Not being able to take it anymore Sephirah clung to her little sister and finally let her despair & happiness out: Despair for how life hates her and happiness for someone who loves her.

Her mother watched ecstatic at how her oldest daughter had finally shown emotion after all this time. To her this was absolutely the best day of her life.

The little sister simply snuggled in deeper in her older sister's embrace and cooed at her.

It was then that Sephirah made a promise: She would always be there for her, to protect her, to love her… and she will destroy and kill ANYONE & ANYTHING that would dare try to take her happiness away.

Even if that threat… was her own mother… or her own sickly sister.

* * *

Author's Notes

Alright here's my first triple crossover of High School DxD/Final Fantasy & Nasuverse!

Also this is my second Yuri fic so if you don't like it then just go away!


	2. Delinquent Angel & the Nun

Chapter 1: Delinquent Angel & the Nun

 _I remember…_

 _The days that were once happy…_

 _The day that were once peaceful…_

 _The days with my sisters…_

 _The days with my mother…_

 _Friends, family…_

 _I so wish that they could have lasted longer…_

 _Why did my friends have to leave…?_

 _Why was my mother so weak…?_

 _Why was my elder sister so cruel…?_

 _Now all that's left are memories, blood, and tears…_

* * *

Alarm clock was blaring loudly, she tried to ignore it and go back to sleep despite the memories she had. It still kept blaring till finally…

"GODDAMMIT ALREADY WILL YOU SHUT UP!"

The young woman threw the alarm clock out the window. The young 17 year old woman got off the bed irritated. She was quite beautiful, can definitely be considered a top beauty, with large breasts, wide hips, long pink hair and bright violet eyes it wouldn't be an exaggeration to say that she had the beauty of a goddess. Though it was somewhat ruined with the scowl and hardened look on her face. This was Aiko Nonaka.

"Big sister breakfast is ready! Hurry up before you're late for school!"

She flinched hearing her younger twin sister mention school. If she had her way then she wouldn't go to school PERIOD except… she had no choice. Not if she wanted to support her dear sister…

She quickly dressed up, now wearing a small white & purple t-shirt that resembled more like a bra than anything else, a violet hoodie, a black short skirt and black leggings and her hair tied into a ponytail.

She quickly got out of her room preparing for the usual hell like always.

* * *

"Big sister please tell me you didn't chuck the clock out the window again."

Setting up the table for them was Aiko's younger twin sister Sora. In all honesty the only difference between the two were that Sora's eyes were a bluish green, was SLIGHTLY shorter, and lacked the hardened & anger look that her sister always sports.

In other words Aiko was a raging volcano while Sora was a calming pond.

"All right…"

The two stared at each other before Aiko giggled.

"But I can't though."

Sora simply rolled her eyes though she did smile in amusement.

The two ate happily in silence at least for a moment however Sora then noticed something.

"Big sister… You had that dream again didn't you…"

The good mood was gone as Aiko's smile turned into a frown.

"I-If I wasn't so weak… then you-!"

"DON'T Sora…"

Aiko let out a sigh.

"It was I that made the choice, not you. You're completely innocent in all this."

Sora looked like she wanted to argue more however one pleading look cause her to fall into silence.

They ate silently though the mood was a bit more somber.

Aiko looked at the clock and saw the time.

"Shit I'm gonna be late."

She quickly ran to the door.

"Big sister promise me you won't hurt anyone very badly this time!"

"No promises!"

Sora sighed in defeat knowing that more people were about to be sent to the hospital.

* * *

Aiko was opening her garage and getting out her bike that she liked to call Fenrir. It was a three-wheeled (two paired up in front and one in the rear) motorized vehicle with a combination of polished black metal over brushed gold mechanics and on either side of the front tires was an expandable compartment.

Aiko smirked happily as this bike was practically made for her, it annoyed the Student Council President every time she rode it to school, and it always scared the crap out of her fellow students.

Revving up the engine she quickly drove off to school.

While riding she took in her sights. Everything was quite advanced having what others may considered a futuristic look to it, and it was all thanks to a certain company.

Stopping before a red light, Aiko noticed a logo that instantly caused her to scowl.

SHINRA

A multinational industrial enterprise that mainly focuses on power than anything else. It was thanks to this company that the world was so advanced due to them discovering an energy deep within the Earth called Mako. This company was so successful that it even gained substantial power over politics and societies around the world. It's also known for delving into engineering & genetics. What not many people know, except for Aiko & Sora, is that SHINRA has their own private military called SOLDIER that's used to enforce SHINRA's will on others.

Thinking about SOLDIER caused her to scowl in disgust and sadness knowing that the program was what practically ruined her life. Though it was too late now for any regrets, she made her choice and she wouldn't change it at all.

With the light going green, she once again rode off to school.

Arriving to school, while scaring some newbies much to her amusement, she parked her bike before heading inside, or at least would have if it weren't for a group thug-wannabe students that were getting in her way.

"Oi Aiko! We have a bone to pick with you!"

"Yeah! Today's the day where we finally show you your place!"

Aiko simply looked at them with boredom in her eyes before she lazily grinned at them though her eyes spoke of annoyance.

"Great not another group of idiots…"

"You'd think they'd learn by now…"

"We'd better get out of here…"

Everyone who had gotten used to seeing this immediately left the area while some immediately got buckets full of water and mops so they could clean up all the blood that was sure to be shed.

Loud screams of terror & pain echoed throughout the entire school…

* * *

"Geez did you really have to be so violent so early?"

"Oh come on! Those idiots were asking for it!"

Aiko could be seen talking with another girl whose figure could easily match her's. She had long blackish-brown hair that falls below the waist & tied at the tips to form a dolphin-tail split, while her eyes were a brownish-red colour.

This was Tifa Lockhart one of Aiko's childhood friends until she had to move away.

"I know that but couldn't you have… held back a bit?"

"Nope."

Tifa simply sighed in exasperation.

"Hey guys wait up!"

Running towards the two was another girl with the same body type as them though she had long light-blonde hair around the same length as Tifa, and had blue-grey eyes.

This was Yumi Kiba, the 'Princess' of Kuoh Academy and perhaps the only true friend that Aiko has other than Tifa.

"Hey Princess, finally managed to escape your adoring subjects?"

Yumi nearly tripped herself before glaring at her with pouted cheeks.

"Hey you have no idea just how rabid those fanboys really are!"

Aiko simply laughed at her in amusement and even Tifa giggled at Yumi's situation, causing her to pout even more before that changed to a lighthearted smile as the three talked with each other about some tuff that interested them though mostly about how Aiko keeps attracting trouble. If there was one positive about going to school it was this.

Too bad for her that these peaceful days would soon be over as well as the demons of her past will find her & her sister once more…

* * *

"Are you sure Buchou?"

Both Yumi and Tifa were looking at their club president with questioning/nervous looks. Their club president being a curvaceous woman whose body easily surpassed the two, had long crimson hair and bright blue-green eyes.

Rias Gremory: the number 1 most popular girl of the Academy and one of 'Kuoh's Great Ladies.'

"Yes, I'm sure about it Tifa, Yumi… Aiko has a Sacred Gear, and a powerful one at that."

The two girls sighed in reluctant acceptance. They did not want Aiko to get involve in all this, however if she has a Sacred Gear then she will get involve in all this.

"Aiko has already suffered enough… why did she have to be born with this burden."

Despite Tifa leaving she had kept in contact with Aiko throughout the years so she knows of her situation (or at least a part of it)… as well as the change of her identity.

Yumi didn't know, however she could easily see the darkness in Aiko's eyes that matched her own as well as the burden she carries.

"Don't worry you two."

Rias turned towards the two.

"Even if the Sacred Gear turns out to be a weak one I'll try to have her in my Peerage so she'll have the protection of the Gremory family."

Both Yumi & Tifa smiled in relief. They knew that it was asking too much for Rias to reincarnate Aiko but it was the best they could do.

They had no idea how soon that will happen…

* * *

School was over and the sun was setting.

Besides this morning's 'slaughter' her day was surprisingly peaceful though she knew for a fact it won't last long.

"Hm?"

She noticed a black feather floating down from the sky. She instantly went on guard before picking it off.

She instantly relaxed when she carefully examined it.

'Still what kind of bird leaves a feather like this?'

She had no idea why, but she simply decided to pocket it for some reason.

If she had looked up she would have seen four figures flying high up in the sky in quite a hurry as if they were searching for something… or someone…

* * *

Aiko was walking home currently deep in her thoughts. That feather honestly brought unpleasant memories to mind.

'Though I do wonder, if it's perhaps for the better that I do remember them…'

"Hawaau!"

Hmm?

She turned back and saw a Nun laying on the floor, most likely having tripped on something.

She went over to help the nun up.

 _"Auu. Why do I keep on tripping over… Oh, I'm sorry. Thank you very much~."_

Judging from the voice she was pretty young, maybe younger than she is, and she also happens to speak Italian.

Suddenly the wind blows carrying off the nun's veil.

Her blonde hair, which was hidden underneath, falls down onto her shoulders sparkling with light because of the sunshine, and sparkling green eyes full of innocence.

'Well you don't see a person like that everyday. Might even beat Yumi in the princess category.'

Snapping out of her daze she quickly snatched the veil and handed it back to her.

 _"T-thank you."_

 _"Ah no problem at all."_

'Guess those language lessons paid off after all.'

Asia look pleasantly surprised that someone else spoke her language.

Aiko then noticed that the nun is carrying a travelling bag with her.

 _"You travelling or something?"_

 _"No, that's not it. My sister sent me here with some friends, though I got separated from them and am now currently lost."_

 _"I see, do you happen to know where you guys were supposed to meet?"_

 _"We were supposed to meet at this town's old church… however I don't know where that is, and no one understands me."_

'Right, my older sister and I are probably the very few here in this town that are bilingual.'

Though she wanted to get home quickly she couldn't very well leave the nun here all by herself. She practically screamed 'easy prey.'

 _"You know I happen to know where the church is."_

 _"Eh? You do?"_

 _"Yeah I'll take you there if you want. Can't just leave you here all by yourself after all."_

 _"Y-you will? T-Thank you~! This is all thanks to God!"_

She smiles at her with tears flowing from her eyes.

 _"Jeez no reason to cry like that."_

Aiko smiled.

* * *

"Goddammit! Where is she?!"

At the abandoned church there were three figures resting a bit after long hours of searching.

One was a young woman with violet eyes, long silky black hair, a slender body with a large bust, and her clothing consisted of black, strap-like objects (resembling leather) around and under her breasts, a thong-like piece held around her hips by three thin straps, gloves that ran right up her arms with small lengths of chains hanging from them, shoulder guard-like objects on her shoulders with three large spikes sprouting from her right shoulder, and black thigh-high heel boots. This was Raynare, the unofficial leader of this group.

The second was a tall and buxom woman with brown eyes, long navy blue hair that obscured her right eye, her attire consisting of a maroon, trenchcoat-like top with a wide collar with the top open at her chest giving view to her breasts and cleavage, a matching miniskirt, and also wore a gold necklace around her neck. This was Kalawarner, the unofficial second-in-command.

The third and final one was nowhere near as curvaceous as her two companions as she was a young girl with blonde hair styled into twintails, blue eyes, with her attire consisting of a black Lolita dress with white frills, a large black bow on the front, and a green jewel embedded on the collar, white thigh-high socks, black shoes, and a large black bow on top of her hair. This was Mittlet, the youngest of the trio.

The three right now were in a bit of a crisis as they were supposed to take care of Asia Argento till her sister came however somehow they ended up losing her and have searched the entire town yet they still couldn't find her.

"We probably wouldn't have lost her in the first place if SOMEONE hadn't got distracted by some ice-cream."

Kalawarner gave Mittlet a withering glare, while Mittlet just chuckled sheepishly.

"Hey! I was hungry and the ice-cream happened to be free!"

Raynare rolled her eyes in exasperation at the two arguing.

"Will you two knock it off!"

The two stopped arguing.

"… She started it."

Mittlet grumbled.

"Look now's not the time to act like a bunch of immature brats; we still have to search for Asia and if we don't find her than Fia is going to beat the crap out of us if she finds out."

At the last statement all three shivered in fright. If there's one thing you do NOT want it's to have an angry Fia Argento after you.

Before more could be said they heard the church doors open.

 _"Um is anyone in here?"_

 _"Asia!"_

Raynare quickly grabbed Asia into a hug, unintentionally suffocating the poor girl into her large bosom.

"Um… Raynare I think you're suffocating the poor girl."

Kalawarner deadpanned while Mittlet twitched in jealousy at the reminder of how small in the chest department she is.

"Huh? Oh! Whoops…"

Raynare instantly let go of Asia who instantly took large gulps of air.

 _"I thought I was going to die…"_

Kalawarner snickered.

 _"Sorry about that Asia; anyway where were you? You had us all worried sick!"_

 _"I'm sorry everyone I don't know how I got separated from all of you .I was lost for some time until I met kind person who can speak my language."_

At this Raynare slapped her forehead, she completely forgot to implant a translation spell on Asia so she could understand other languages.

 _"She guided me towards the church as well as showing me around town so I wouldn't get lost again. Her name is Aiko Nonaka."_

Asia smiled in remembrance.

 _"I see, well if we end up meeting her than I'll be sure to thank her for helping you in your time of need."_

'Plus thank her for saving our assess.'

Raynare thought.

 _"Um, Lady Raynare?"_

 _"Yes what is it Asia?"_

 _"Will it be ok if Aiko visits from time to time?"_

Raynare raised an eyebrow and looked at the others who simply shrugged.

 _"I honestly don't see why not."_

'Plus it'd be good for her to make more friends.'

 _"Really?"_

Asia looked hopeful.

 _"Yes, although it would best that you kept the fact that the rest of us are fallen angels to your new friend."_

 _"Yes Lady Raynare!"_

Asia looked absolutely happy.

Raynare smiled at Asia's giddiness.

'Things are about to become quite interesting.'

* * *

Author's Notes

Well here's the first chapter of One-winged Angel of Gremory!

As you can see our main character has made contact with everyone's favourite nun, the Fallen Angel girls are not evil, and oh what's this? Asia has a sister!

Aiko has a Sacred Gear however IT IS NOT the Boosted Gear (someone else has that and she'll be somewhat familiar to you guys and takes a certain loveless soldier' place in this fic)

Before anyone asks yes Aiko & Sora are those same twins from the prologue.

The reason why Aiko & Sora aren't with their mother or older sister will be explained at later chapters though you guys are free to guess what those reasons are.

Aiko will be a part of Rias' peerage yet at the same time not; if you guys are confused than here's a hint: Materia

Asia won't be a part of Rias' peerage.

There will be incest.

This is perhaps going to be one of my longest fics ever as there will original arcs, the Trihexa arc will be MUCH longer, as well as I will add the events of Crisis Core, Advent Children & Dirge of Cerberus (the latter two will happen after the Trihexa arc)


End file.
